GM Service Manual Online
For 1990-2009 cars only

Caution: Place a dry chemical (Class B) fire extinguisher near the area before performing a Fuel Tank Leak Check. Before removing the fuel tank for a suspected leak, make sure that the fuel pipes or the tubes are not leaking onto the tank. Once removed, make sure that the fuel is not leaking around the fuel sender O-ring. Failure to follow these precautions may result in personal injury.

  1. Drain the fuel tank. Refer to Fuel Tank Draining .
  2. Remove the fuel tank. Refer to Fuel Tank Replacement .
  3. Plug the fuel feed hose, the fuel return pipe, and the fuel vapor pipe on the fuel tank.
  4. Plug the fuel filler neck and the fuel breather neck openings.
  5. Connect a piece of the hose to the breather hose nipple on the fuel tank, and secure the hose with one clamp.
  6. Submerge the fuel tank in water, or apply a soapy solution to the outside of the tank.
  7. Apply 7 to 15 kPa (1-2 psi) of air pressure to the breather hose.
  8. • Any air bubbles escaping from the fuel tank indicates a leak.
    • Replace the fuel tank if the tank is leaking.